Anchor for mortise and tenon joint



Jan. 16, 1951 w. R. BROWN ANCHOR FOR MORTISE AND TENON JOINT Filed July 20, 1949' Inventor CHAIR LEG Wesley R. Brown CHAIR ROUNIIVD Patented Jan. 16,1951

UNITED STATES PATENT OFFICE ANCHOR FOR MoR'rIsE AND TENON JOINT Wesley R. Brown, Emmett, Idaho Application July 20, 1949, Serial No. 105,842

. p i 1' I The present invention relates to safety an-' choring and fastening means for use in conjunction with complemental members joined with one another through the medium of a so-called mortise and tenon joint.

I These types of anchors are sometimes referred to 'as radially expandible or projectable and the locking efiect is obtained by forcibly driving the tenon into the mortise socket and causing the anchor, which is mounted in the tenon, to project'beyond the tenon and anchored in the wall of the socket at the time the tenon is fully driven It will be evident from the foregoing statements that I am aware that providing an automatically projectable anchor or fastener on a drive fit tenon, dowel or the like is not new and that it is common practice to use these types of anchors on chair rungs, table legs, ladder cross-rungs and the like. Therefore, I aim, in carrying out the principles of my invention, to provide a specifically and structurally distinct anchor and to provide, in addition, an unusual arrangement of slots or kerfs in the tenon, whereby the slot means attains the desired projection for the anchor and, once in place, prevents a slotted tenon from becoming easily disconnected from the part or member to which it is attached.

More specifically, novelty is predicated upon a tenon having cruciform slot means wherein certain of the slots are inclined in respect to the longitudinal axis of the tenon in a manner to provide inclined planes which serve to cam the coacting anchor to its projected anchoring position.

Another object of the invention is to provide a simple and practical metal or equivalent anchor, the latter characterized by a comparatively sturdy plate carrying an outstanding flange, said flange being provided on its effective edge with anchoring prongs, the plate being provided with an impact abutment overhanging one end of the flange.

Other objects and advantages will become more readily apparent from the following description and the accompanying illustrative drawings. 7

In the accompanying sheet of drawings:

Fig. 1 is a fragmentary sectional view, with parts in elevation, showing one member with a mortise socket, another member with a slotted tenon, and the improved anchor associated with said members;

3 Claims. (Cl. 2092) Fig. 2 is a horizontal section on the plane of Fig. 4 is a perspective'view of the anchor or fastener per se; and,

Fig. 5 is a view similar to Fig. 2 and intended to show how the device is used in conjunction with a chair leg and an associated right angularly disposed round.

Referring to the drawing by numerals and lead lines and with reference 'to Fig. 4 wherein the anchor per se is disclosed. This element is denoted by the numeral 1 and comprises a substantially flat rectangular plate 8 having a laterally bent end 9 constituting anabutment. The numeral Ii! designates the complemental flange which is at right angles to the central portion of the plate and is welded or otherwise connected thereto, as at ll. It may be stated that the parts 8 and Ill may be made separately and welded or cast in one piece, as is obvious. The free edge portion l2 of the flange is provided with pointed anchoring prongs I3 and M respectively. It will be noted that the stated abutment 9 overlies the adjacent transverse end 15 of the flange. However, the flange projects well beyond the edge l6 of the abutment.

The numeral. I! in Fig. 1 represents what may be visualized as a table top and I8 denotes a leg whose end, the stated tenon, is adapted to fit telescopically and snugly into the mortised socket [9 in the table. As shown in Fig. 3 the tenon has a cruciform arrangement of slots. Although this arrangement may be described as made up of four kerfs or slots, I propose to visualize the same as made up of two intersecting slots, one denoted by the numeral 20 and the other by the numeral 2!. The slot 20 open through one end of the tenon and also through diametrically opposite sides of the tenon and said slot is straight from end to end and centrally arranged and in alignment with the longitudinal axis of the tenon. Intersecting slot 2| is inclined toward the left as shown in Fig. 3 and at the desired angle and by so inclining this slot the walls or surfaces 2222 and 23-23 are also inclined. It will simplify matters to assume that the walls 23 are inclined planes or cams and serve to provide the desired camming of the fastener I from right to left in Fig. 1. The plate 8 fits into the slot 2i and the flange l2 fits into a half portion of the slot 29, but that is the half portion to the left in the drawing. In practice the plate is positioned partly in said slot 2| with the flange IE! and abutment it projecting beyond the end of the tenon a short distance. At this stage the position of the plate in the slot is such that the prongs I3 and I4 recede into slot means 20. However, and as the tenon is driven home into the mortised socket, it is evident that when the abutment I6 comes against the bottom of the socket, continued driving of the tenon into the socket will bring about the desired camming action and consequently will project the prongs I3 and I4 through the slot means 20 and anchor same in the wall of the socket as illustrated in Fig. l.

A careful consideration of the foregoing description in conjunction with the invention as illustrated in the drawings will enable the reader to obtain a clear understanding and impression of the alleged features of merit and novelty suflicient to clarify the construction of the invention as hereinafter claimed.

Minor changes in shape, size, materials and rearrangement of parts may be resorted to in actual practice so long as no departure is made from the invention as claimed.

Having described the invention, claimed as new is: I

1. A mortise and tenon joint and fastener comprising, in combination, a body member having a mortise, a leg having a tenon fitting telescopically into said mortise, said tenon having intersecting slots, there being a cruciform arrangement of said slots, one of said slots being inclined in respect to the longitudinal axis of said leg and providing inclined planes, and a fastener embodying a plate fitted in said one slot and angled to a slanting position by said inclined planes, said plate carrying a right angularly disposed flange fitted in a portion of the remaining slot and having prongs projecting what is 0 Number from an edge and anchored in a co-acting wall of said mortise.

2. In a structure of the class shown and described, a leg having a pair of lengthwise slots formed in one end portion of said leg, said slots intersecting one another and defining cruciform slot means, one slot being in axial alignment with the longitudinal axis of said leg and the other slot being inclined with respect to said axis and providing cam surfaces, and a projectable fastener comprising a plate slidably mounted in said inclined slot, and a flange integral with said plate, said flange being centrally joined to said plate and at right angles to latter and being provided on an outer edge with anchoring prongs.

'3. The structure specified in claim 2 wherein said plate is rectangular and is provided at its outward end with a lateral bend defining an impact element, said impact element projecting to a position beyond the slotted end portion of said leg and overhanging the adjacent end portion of the flange.

' WESLEY R. BROWN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date 1 Scarritt Mar. 12, 1878 Thompson etal. June 14, 1892 Arnold May 12, 1896 

